Evinrude 4906B 4HP 1969, Owner'S Manual

Page: 13 / 422

1-8 SAFETY
Taking On Fuel
The fuel tank of your boat should be kept
full to prevent water from entering the
system through condensation caused by tem-
perature changes. Water droplets forming is
one of the greatest enemies of the fuel
system. By keeping the tank full, the air
space in the tank is kept to an absolute
minimum and there is no room for moisture
to form. It is a good practice not to store
fuel in the tank over an extended period, say
for six months. Today, fuels contain ingre-
dients that change into gums when stored
for any length of time. These gums and
varnish products will cause carburetor prob-
lems and poor spark plug performance. An
additive (Sta-Bil) is available and can be
used to prevent gums and varnish from
forming.
Static Electricity
In very simple terms, static electricity is
called fr icti onal electr ici ty. It is generated
by two dissimilar materials moving over
each other. One form is gasoline flowing
through a pipe or into the air. Another form
is when you brush your hair or walk across a
synthetic carpet and then touch a metal
object. All of these actions cause an elec-
trical charge. In most cases, static electri-
city is generated during very dry weather
conditions, but when you are filling the fuel
tank on your boat it can happen at any time.
Fuel Tank Grounding
One area of protection against the build-
up of static electricity is to have the fuel
An OMC fuel tank equipped with
a
quick-disconnect
fitting. This
type of
arrangement is handy when the
tank must be removed from the boat to obtain fuel.
Old style pressure-type tank showing the fuel line to
the engine and quick-disconnect fitting.
tank properly grounded (also known as bond-
ing).
A direct metal-to-metal contact from
the fuel hose nozzle to the water in which
the boat is floating. If the fill pipe is made
of metal, and the fuel nozzle makes a good
contact with the deck plate, then a good
ground is made.
As an economy measure, some boats use
rubber or plastic filler pipes because of
compound bends in the pipe. Such a fill line
does not give any kind of ground and if your
boat has this type of installation
and you do
Adding fuel
to a
six-gallon OMC fuel tank. Some
fuel must
be
in the tank before oil is added
to prevent
the oil from accumulating on the tank bottom.